The overall goal of this proposal is to examine changes in motivation, beliefs, and behaviors related to pursuing careers in biomedical and behavioral science among Hispanic high school students. The proposal's key innovations include access to an underrepresented minority population at a critical educational stage, testing an important social scientific theory of educational achievement (Phelan, Davison, and Yu's multiple worlds framework) in this context; and application of a longitudinal multi-site mixed-methods design that will produce richer quantitative and qualitative data than typical studies. The multiple worlds framework posits that students act simultaneously in at least 3 worlds, characterized by their academics, their family, and their peers. Our primary research question asks whether Phelan's model provides the ability to describe and predict educational trajectories leading to the ability to pursue scientific careers. The project has three specific aims: 1. To describe and compare longitudinal trajectories of motivation to pursue biomedical/behavior science pathways among Hispanic students compared with students of other ethnicities at five Chicago high schools. We hypothesize significant differences among students of different ethnicities and in different educational programs. 2. To examine parental knowledge and attitudes toward careers in biomedical/behavioral science research among Hispanic students, and describe associations between parental characteristics and student trajectories. We hypothesize that differences in trajectories among Hispanic students will be strongly associated with parental understanding of the nature of scientific work. 3. To examine social-network relationships between students' trajectories and those of their peers. We hypothesize that students will tend to resemble their peers in their educational trajectories, even controlling for parental characteristics, and that strong connections to peers will independently facilitate or deter scientific education (depending on the constellation of values in the peer group).